1. Field of the Invention
This invention relates to power supplies, and more particularly relates to the recording of power supply faults and recording data describing the operating conditions during which a power supply fault occurs.
2. Description of the Related Art
A power supply, sometimes know as a power supply unit or PSU, is a device or system that supplies electrical or other types of energy to an output load or group of loads. A power supply, in some embodiments may be configured to convert power in one form to another form, such as converting AC power to DC power. The regulation of power supplies is typically done by incorporating circuitry to tightly control the output voltage and/or current of the power supply to a specific value. The specific value is closely maintained despite variations in the load presented to the power supply's output, or any reasonable voltage variation at the power supply's input.
In a computer, the power supply is typically designed to convert an AC voltage input such as is traditionally provided by a conventional wall socket, into several low-voltage DC power outputs for transmission to the internal components of the computer. Conversion is typically performed in stages that may include various stages such as a rectification stage, a boost or buck stage, and a regulator/chopper stage. Conventional power supplies, implement very little if any monitoring and data storage capabilities within the power supply which can make it difficult to diagnose an error or fault in the power supply without some additional information from an external system or memory.
This can be a problem because when a power supply fails while being used in the field, the power supply is often returned to the manufacturer for diagnosis. However, a large percentage of returned power supplies result in a no defect found “(NDF)” meaning that the manufacturer was unable to find a defect in the power supply. The cost for diagnosing power supplies believed to be faulty, but which are actually not faulty, can be extremely expensive.
Furthermore, there is no record of failure codes, hours of operation, power ON/OFF cycles, the event and the time of occurrence of a power fault, and there is no conventional mechanism to determine the power consumption data in real time which can be crucial to determining the environmental conditions of the power supply at the time of a failure. In existing solutions, only the fault codes are reported to the system powered by the power supply, and such information is not recorded within the power supply itself. Thus, when a power supply is returned to the manufacturer, there is no actual record of the faults saved, nor the operations being performed when the fault occurred, nor the POWER-ON Hours “(POH)” that the power supply was in use. In rare embodiments in which a power supply does store recorded operation data in the power supply, such operation is limited to POH data that is stored in a memory outside of power supply's microcontroller which means that two addresses are needed to communicate with the microcontroller and the memory. Furthermore, such an implementation can be extremely expensive and may require very complex circuitry.
Thus, there is a need for a power supply that includes an inexpensive memory integrated within a power supply microcontroller for monitoring, recording, and reporting the operating conditions of the power supply, and particularly recording the operating conditions of a power supply at the time of and immediately preceding a failure.